The present invention relates to a wide-angle zoom lens system for a still camera which is small, compact and has a large aperture.
U.S. patent application Ser. No. 794,589, assigned to the assignee of this application and based on Japanese patent application No. 51-52238, disclosed an extremely compact wide-angle zoom lens system which is a so-called two component-type lens system. In this lens system, however, the aperture ratio is at best 1:3.5. With increasing interest in available light photography, there is a demand for faster or brighter lenses, that is larger aperture lenses. If the aperture of the lens system disclosed in U.S. patent application Ser. No. 794,589 were to be increased, the curvatures of the lens surfaces would have to be increased to maintain the compact size of the lens system. Consequently, aberrations of the lens system would be worsened, and this is especially true of the spherical aberration and coma flare in the telescopic range of the lens system.